Starter drive



June 2, 1931. w, MCGRATH STARTER DRIVE Filed Sept. 10, 1929 2Sheets-Sheet 1 INVENTOR Y William L. M Grail: B l/ June 2, 1931. w, lMcGRATH STARTER DRIVE.

Filed Sept. 10, 1929 2 shet-sheet 2 M M r N m Id T L P W6 A, C v

9 2 M/ 7 L w 07 .m N F u 3 W 3 Y B Z 4 3 5 5 Q N Patented June 2, 1931UNITED STATES PATENT OFFICE WILLIAM L. MCGRATH, 0F ELMIRA, NEW YORK,ASSIGNOR TO ECLIPSE MACHINE COM- PANY, OF ELMIRA, NEW YORK, ACORPORATION OF NEW YORK STARTER DRIVE Application filed September 10,1929. Serial No. 391,641.

This invention relates to starter drives for internal combustionengines, and more particularly to a starter drive including a manualshift for a starter pinion.

One object of the present invention is the provision of a novel starterdrive which is positive and eflicient in operation and'economical tomanufacture.

Another object of the invention is the provision of a novel positiveone-way driving means for a starter pinion which is adapted to releaseand allow the pinion to over-run freely without jamming.

A further object is to provide a starter drive, the parts of which maybe formed by economical machining methods, and do not require a highorder of acuracy in the formation thereof.

Other objects and advantages will be apparent to those skilled in thisart from the following description taken in connection with theaccompanying drawings in which:

Fig. 1 is a side elevation of one embodiment of the invention;

Fig. 2 is a vertical section taken substantially on the line 22 of Fig.1, with parts shown in driving relation;

Fig. 3 is a vertical section similar to Fig. 2 showing the parts inover-running relation;

Fig. 4 is a view similar to Fig. 1 of another embodment of theinvention;

Fig. 5 is a vertical section taken substantially on the line 5-5 of Fig.4 with the parts in driving relation; and

Fig. 6 is a vertical section similar to Fig. 5, showing the parts inover-running relation.

Referring first to Fig. 1 of the drawings, a power member in theform ofa driving shaft 10 which may be the armature shaft of a starter motor,or any other suitable power shaft is shown having a portion thereofprovided with straight splines 11, and being provided beyond the splinedportion with a reduced smooth portion 12. An internally splined shiftersleeve 13 is mounted to slide freely upon the splined portion 11 of thedriving shaft 10 and has a radial flange 14 formed at the end thereofadjacent to the smooth portion 12 of shaft 10. An annular driving clutchmember 15 provided with internal teeth 16 is adapted to be fixed againstthe periphery of flange 14 in an suitable manner as by means ofinter-fitting shoulders 17 and 18 formed respectively on the flange 14and ring 15, and rivets 19 passing through the flange and ring.

A starting pinion 20 is rotatably and slidably journaled on the smoothportion 12 of shaft 10, and is provided with a cylindrical eccentricportion 21 adapted to be positioned within the annular member 15. Athimble 22 which may preferably be formed of a bearing alloy is fixed onthe eccentric portion 21 of pinion 20 as by being pressed thereon, andis provided with a radial flange 23 which is concentric with the drivingshaft.

An intermediate clutch or transmission member 24 in the form of ainionis journaled freely upon the thim le 22 and is provided w1th teeth 25adapted to cooperate with the teeth 16 of the annular clutch member 15,the relative sizes of the transmission member and annular member beingso arranged that if the cooperating teeth 25 and 16 were formed asordinary symmetrical gear teeth, these two elements would cooperate asplanetar eccentric gears and rotate freely in eit er direction. It willbe noted however, with special reference to the showing in Fig. 2, thatwhereas the teeth of the two clutch members are each formed on one sidethereof with appropriate tooth contours for free running together, thaton the opposite sides thereof the teeth are cut away in an approximatelyradial direction so that suflicient back-lash is introduced to allow theends of the teeth to come into abutting relation as shown at 26 in Fig.2 when the annular clutch member 15 is rotated with respect to theclutch member 24 in the direction of the arrow (a) there illustrated. Itwill be seen that this abutment of the ends of the driving and driventeeth 20 the latter is also positively connected to the clutch member 15for rotation therewith in one direction. g

A shift collar 27 of any suitable form is loosely mounted on theexterior of the shift er sleeve 13, being retained thereon by suit ablemeans such as a split ring 28 mounted in the shifter sleeve and adaptedto seat in a recess 29 in said shift collar. The shift collar isnormally maintained in contact with times for longitudinal movement withthe shifter sleeve 13.

In operation, when it is desired to start the en ine the shift collar 27is moved to the le t in Fig.- 1 by any suitable manual shifting meansnot shown, thereby causing the pinion 20 to move longitudinally intomesh with the flywheel gear of the engine indicated at 33. The switch ofthe starting motor is thereupon closed, causing the motor to rotateshaft 10 in the direction of the arrow (a) in Fig. 2. Rotation of shaft10 is transmitted through the splines 11 to the shifter sleeve 13 andclutch member 15, which thereupon engages the clutch member 24 asindicated at 26 in Fig. 2, thus rotatin clutch member 24 and pinion 20to cran the engine. When the engine starts under its own power, thepinion 20 is driven b the flywheel 33 at high speed, but the clutcmember 15'is not compelled to rotate with the pinion 20 since thetransmission member 24 planetates idly within the clutch member 15allowing the pinion 20 to overrun freely, as indicatedby the arrow (6)in Fig. 3. This condition is maintained until the pinion' 20 iswithdrawn from engagement with the flywheel 33 by the operator restoringthe shifter parts to normal position.

It will be readily appreciated from a consideration of the structure andoperation of this device that the cooperating clutch ele ments are notdependent for their successful operation on any high degree of accuracyin the formation thereof.

It will further be noted that by reason of the driving engagement of theclutch members being a substantially normal engagement of flat surfaceson the ends of the teeth, there is no tendency to wedge and jam theclutch members. Over-running of the pinion is, therefore, allowed totake place freely without transmitting any substantial acceleratingforce to the armature shaft of the starting motor.

In the embodiment of the invention illustrated in. Figs. 4, 5 and 6, amotor shaft 10 is provided with splines 11 and a reduced smooth portion12. A shifter sleeve 13 is splined on the shaft and is provided with ashift collar 27 loosely mounted thereon and retained by suitable meanssuch as a split ring 28 seated in a groove in sleeve 13 and adapted tobe received-in an annular recess 29 in the shift collar. The shiftcollar is yieldably held ,against the retaining ring 28 by suitablemeans such as a spring 30 bearing at one end against the collarand atthe other against a radial-flange 14 on the end of sleeve '13.

An eccentric member 40 is loosel mounted on the smooth portion 12 of shat 10; This member comprises an extension 41 concentric with shaft 10,forming a seat for the end of shifter sleeve 13, a radial flange 42 alsoconcentric with the shaft, adapted to be suitably fixed to the flange 14of sleeve 13 as by means of rivets 43, and'a cylindrical eccentricortion 44.

A pinion 45 is sli ably mounted on the shaft 10 adjacent the eccentricmember 40,

and a casing 46 is adapted to be mounted on the end of the pinion, beingsplined thereto by inwardly extending teeth 47 on the casing formed tointerfit with the teeth of the pinion 45, and being retained on thepinion by suitable means such as .a ring member 48' fixed to the end ofthe pinion as indicated at 49. The casing 46 is adapted to extend overthe eccentric member 40, loosely surrounding the peripheries of the flanes 42 and 14, which are suitably retained t erein as by means of a splitring 50 seated in the end of the casing.

An intermediate transmission or clutch member 51 in the form of aplurality of laminations having asymmetrical peripheral teeth 52 asabove described in connection with the first embodiment of the inventionis freely journaled on the eccentric portion 44 of member 40. A drivenclutch member 53 in the form of a plurality of laminations havinconjugate. asymmetrical internal teeth is mounted withln the casing 46and non-rotatably connected thereto as by means of the interfitting ribs55 and depressions 56 formed in said casing and laminationsrespectively.

The operation of this embodiment of the invention is substantiallysimilar to that previously described. When the operator moves theshifting collar 27 to the left in Fig. 4 by the usual pedal mechanism,not shown, the pinion 45 is meshed with flywheel 33'and thereafter themotor is energized to rotate shaft 10. Rotation of shaft 10 istransmitted through sleeve 13 and rivets 43 to eccentric member 40,which,

. ings and involve no ex turning in the direction of the arrow in Fig.5, moves the driving clutch member 51 ,into driving engagement with thedrivenclutch member 53 to overrun the drivingclutch member 51 in thedirection of the arrow as shown in Fig. 6. Since this overrunningconstitutes in effect simply the meshin of a pair of unloaded internaland externa spur gears, and since the only torque transmitted backthrough the clutc to rotate the motor shaft is the result of the slightbearing friction of the clutch member 51 on the eccentric member 40, itis obvious that the overrunning is quiet without any ftsubstantialrotative effect on the motor sha It will be noted that since the clutchparts may be made from stampings and punch enslve machining operationsnor' close fitting, the device is exceptionally cheap to manufacture andeasy to assemble.

It is to be understood that various other embodiments of the inventionare possible and various changes may be made in the construction andarrangement of the parts without departing from the s irit of theinvention. Reference is there ore to be had to the claims appendedhereto for a definition of the limits of the invention.

What is claimed is:

1. A starter drive for internal combustion engines including a memberadapted to enage and rotate an element of the engine to be started, apower member and unidirectional driving means connecting the powermember to the engine engaging member including an annular elementconnected to one of said members, an eccentric fixed to the other memberand an intermediate transmission member mounted on said eccentric andhaving means adapted to interlock with the annular element in onedirection of rotation.

, 2. A starter drive for internal combustion engines including a memberadapted to engage and rotate an element of the engine to be started, apower member, and unidirectional driving means connecting the powermember to the engine engaging member including an internally toothedannular element connected to one of said members, an eccentric fixed tothe other member and an intermediate transmission member journaled onsaid eccentric and having teeth adapted to interlock with the teeth ofthe annular element in one direction of rotation.

-3. A starter drive for internal combustion engines including a memberadapted to engage and rotate an element of the engine to be started, adirectional drivin means connecting the ower member to t e engineengaging memer including an internally toothed annular element connectedto one of said members, an eccentric fixed to the other member and anintermediate transmission member jour naled on said eccentric and havingteeth adapted to positively interlock with the teeth of the annularelement and drive the engine en aging member, but being formed to meshreely therewith to allow the engine engaging member to overrun the powermember.

power member, and uni- I 4. A starter drive for internal combustionengines including amember adapted to engage and rotate an element of theengine to be started, a power member, and unidirectional driving meansconnecting the power member to the engine engaging member including aninternally toothed annular element connected to one of said members, aneccentric fixed to the other member and an intermediate transmissionmember journaled on said eccentric and having teeth provided withcontours on one side adapted to cooperate and cause meshing of the teethas gear teeth in one direction of relative rotation of the parts, butbeing cut away to allow the ends of the teeth to abut and preventrelative rotation in the other direction.

5. An overrunning clutch including driving and driven members, a clutchelement connected to rotate with one ofsaid members, a cooperatingclutch element mounted on an eccentric axis fixed with respect to theother member, said elements having cooperating means formed and arrangedto lock and cause the assembly to rotate as a unit 'in one direction ofdrive while being formed to run together freely in the other directionof drive.

6. An overrunning clutch including driving and driven members, a toothedclutch element connected to rotate with one of said members, acooperating toothed clutch element mounted on an eccentric axis fixedwith respect to the other member, the teeth on said elements having suchcontours that said teeth lock and cause the assembly to rotate as a unitin the normal direction of drive, and formed to run together" freelywhen the driven member overruns the driving member.

An overrunning clutch including driving and driven members, a toothedclutch element mounted to rotate with one of said members, a cooperatingrotary toothed clutch element journaled on an eccentric axis fixed torotate with the other member, the teeth on said elements havingsubstantially flat tops and being provided with such asymmetricalcontours that the ends of the teeth will abut and lock the assembly forrotation as a unit in the normal direction of drive, but the teeth willmesh and run together freel when'the driven member overruns the rivingmember.

8. An overrunning clutch including a driving member, a driven membersubstantially aligned therewith, a toothed clutch element mountedcoaxially on one of said members and adapted to rotate therewith, ajournal bearing mounted eccentric to the othermember and fixed to rotatetherewith, and a toothed clutch element mounted on said bearing andadapted tov cooperate with the first clutch element, tin, teeth on saidelements being formed to lockand cause the assembly to rotate as a unitin one direction of drive, but to run together freely in-the otherdirection of drive.

9. An overrunning' clutch including an internally toothed annularmember, a member having an eccentric portion located therewithin and anintermediate transmission member rotatablymounted on said eccentricportion and having teeth adapted to interlock with the teeth of theannular member in one direction of rotation.

10. An overrunning clutch including an internally toothed annularmember, a member having an eccentric portion located therewithin andanintermediate transmission member in the form of a pinion rotatablymounted on said eccentric portion and having teeth adapted to mesh withthe teeth of the annular member, 'said teeth being formed to lockagainst relative rotation in one direction, butto allow free relativerotation in the-other direction.

11. An overrunning clutch including an internally toothed annularmember, a member havmg an eccentric portion located therewithin and ianintermediate transmission member rotatably mounted on said eccentricportion and having teeth adapted to mesh with the teeth of the annularmember, said teeth having suitable contours on one side for meshing'as'gear teeth in one direc-. tion of relative rotation, but bein cutaway on the other sides whereby the en s of cooperating teeth abut andpositively prevent relative rotation in the other direction.

12. A starter drive for internal combustion engines including a driveshaft, a shifter sleeve mounted to rotate therewith but free to movelongitudinally thereon, a member slidably journaled on the shaft andadapted to engage and rotate a member of the engine to be started, meansconnecting the sleeve and engine engaging member for longitudinalmovement in unison, means under the control of the operator for shiftingthe sleeve to move the engine engagmg member into and out of drivingengagement, and a one way driving connection between the sleeve memberand engine engaging member including an eccentric fixed on one ofsaidmembers, an internally toothed clutch element fixed to the othermember and an intermediate transmission journaled on the shaft andadapted to engage and rotate a member of the engine to be started,interengaging flanges fixed to the sleeve and pimon and connecting thesame for longitudinal movement in unison, means under the control of theoperator for shifting the sleeve to move the pinion into and out ofdriving engagement, and a one way driving connecting etween the sleeveand pinion including an eccentric fixed on one of said members, aninternally toothed clutch ring fixed, to the other member and anintermediate transmission member journaled on said eccentric and havingan annular series'of teeth formed and arranged .to lock with the ringteeth in one direction of relative rotation but to freely mesh therewithin the other direction of relative rotation.

In testimony whereof I have signed this specification.

- WILLIAM L. MoGRATH.

